Encapsulated Detectors

Encapsulated Germanium Detectors for Gamma Measurements
Manufactured by: The Spectroscopy Divison
Favorite this Product

Encapsulated Detectors

Encapsulated Germanium Detectors for Gamma Measurements
Manufactured by: The Spectroscopy Division
Favorite this Product

Encapsulation drastically enhances the germanium detector reliability. This technology is key for many applications, particularly in space, and especially if associated with Ultra High Vacuum. Encapsulated germanium detectors may be easily handled by the users.

Get More Info Data Sheet

Features

  • For compact construction of multi-element detectors for gamma ray applications
  • For very large efficiency and solid angle coverage for high sensitivity and low detection limit gamma ray spectroscopy even in harsh environments
  • Easy annealing in standard ovens, without pumping, in case of radiation damages
  • In situ annealing in space applications
  • Long detector life time
  • Large choice of shapes (pentagonal, hexagonal) for compact matrix assemblies
  • Essential for complex cryostat development, particularly with segmented detectors
  • Total reliability Ultra High Vacuum technology
  • Easy detector handling and exchange

Description

Encapsulation Techniques

Mounting and operation of several detectors in a common vacuum with minimum spacing between consecutive elements makes a real challenge. Encapsulation techniques have been developed to minimize such problems. Placing each encapsulated detector into the vacuum in an individual aluminium cap makes it possible to separate the vacuum of each detector from the cryogenic vacuum shared by all detectors. Encapsulation drastically enhances the germanium detector reliability. This technology is key for many applications, particularly in space, and especially if associated with Ultra High Vacuum. Encapsulated germanium detectors may be easily handled by the users. They may be stored, exchanged or rearranged and be adapted to various applications with different types of cryostats.

A capsule may be regenerated many times and can be thermally annealed in an ordinary oven from neutron or proton radiation damages, without pumping. The life time of such a detector may be estimated to a minimum of seven years without service. But in reality it is much more: The first EUROBALL capsules were delivered in 1992 and are all still in operation. Encapsulated detectors hardness enables a wide application range, such as part of the payload of nacelles, space launchers, etc...

Compact arrays may be designed. The capsules manufactured for EUROBALL offer a typical wall thickness of 0.7 mm with a distance between cap and crystal of only 0.7 mm. These encapsulated detectors may be in contact with one another offering a 3 mm distance between consecutive crystals and a 1.4 mm total aluminium wall thickness.

For better follow-up of scientific progress, some segmented crystals have been encapsulated to offer high granularity, in addition to the previous advantages.

The detector granularity qualifies the number of independent cells constituting this detector. Such detectors allow a significant reduction or gamma ray broadening due to the Doppler effect.

Moreover, the use of internal and external contacts of the crystal provides information on the interacting position:

  • Vertically and transversally, by analyzing signals induced by mirror charges.
  • Radially by making a pulse shape analysis.

Accurate localization of the interaction points allows not only reduction of the Doppler effect broadening, but also gamma ray tracking.

In addition to these benefits, the segmented detector encapsulation allows the design of complex cryostats, thus signal optimization which is of much interest for pulse shape analysis.

The feasibility of the germanium detector encapsulation was studied in the frame of a collaboration between Mirion, the Jülich research center and the University of Cologne in Germany.

Additional Information

Applications

Such a detector is easy-to-use, reliable and robust. So, it may be used in a large range of scientific and industrial applications such as:

  • Array of detectors for gamma spectroscopy (ex: MINIBALL, AGATA, GRETA nuclear physic experiments)
  • Research laboratory – Nuclear medicine
  • Environmental measurements
  • Industrial quality control
  • Homeland Security
  • Space experiments, thanks to its in situ re-generation capabilities after radiation damages (ex.: INTEGRAL, MARS ODYSSEY, SELENE,...)
  • Assistance to Engineers (ex: design of complex cryostats and /or multi elements detector electronic)

Support

Americas
800 Research Parkway
Meriden CT, 06450


Worldwide Support and Sales for Spectroscopy and Waste Characterization products